/*
silverPDF is sponsored by Aleyant Systems (http://www.aleyant.com)

silverPDF is based on PdfSharp (http://www.pdfsharp.net) and iTextSharp (http://itextsharp.sourceforge.net)

Developers: Ai_boy (aka Oleksii Okhrymenko)

Permission is hereby granted, free of charge, to any person
obtaining a copy of this software and associated documentation
files (the "Software"), to deal in the Software without
restriction, including without limitation the rights to use,
copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following
conditions:

The above information and this permission notice shall be
included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR SPONSORS
BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.

*/
#region PDFsharp - A .NET library for processing PDF
//
// Authors:
//   Stefan Lange (mailto:Stefan.Lange@pdfsharp.com)
//
// Copyright (c) 2005-2008 empira Software GmbH, Cologne (Germany)
//
// http://www.pdfsharp.com
// http://sourceforge.net/projects/pdfsharp
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the "Software"),
// to deal in the Software without restriction, including without limitation
// the rights to use, copy, modify, merge, publish, distribute, sublicense,
// and/or sell copies of the Software, and to permit persons to whom the
// Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
// THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 
// DEALINGS IN THE SOFTWARE.
#endregion

using System;
using System.Diagnostics;
using System.Collections;
using System.Text;
using System.IO;
#if GDI
using System.Drawing;
using System.Drawing.Imaging;
#endif
#if WPF
using System.Windows.Media;
#endif
using PdfSharp.Drawing;
using PdfSharp.Fonts.TrueType;
using PdfSharp.Internal;
using PdfSharp.Pdf.Internal;

namespace PdfSharp.Pdf.Advanced
{
  /// <summary>
  /// Represents a shading pattern dictionary.
  /// </summary>
  public sealed class PdfShadingPattern : PdfDictionaryWithContentStream
  {
    /// <summary>
    /// Initializes a new instance of the <see cref="PdfShadingPattern"/> class.
    /// </summary>
    public PdfShadingPattern(PdfDocument document)
      : base(document)
    {
      Elements.SetName(Keys.Type, "/Pattern");
      Elements[Keys.PatternType] = new PdfInteger(2);
    }

    /// <summary>
    /// Setups the shading pattern from the specified brush.
    /// </summary>
    public void SetupFromBrush(XLinearGradientBrush brush, XMatrix matrix)
    {
      if (brush == null)
        throw new ArgumentNullException("brush");

      PdfShading shading = new PdfShading(this.document);
      shading.SetupFromBrush(brush);
      Elements[Keys.Shading] = shading;
      //Elements[Keys.Matrix] = new PdfLiteral("[" + PdfEncoders.ToString(matrix) + "]");
      Elements.SetMatrix(Keys.Matrix, matrix);
    }

    /// <summary>
    /// Common keys for all streams.
    /// </summary>
    internal sealed new class Keys : PdfDictionaryWithContentStream.Keys
    {
      /// <summary>
      /// (Optional) The type of PDF object that this dictionary describes; if present,
      /// must be Pattern for a pattern dictionary.
      /// </summary>
      [KeyInfo(KeyType.Name | KeyType.Required)]
      public const string Type = "/Type";

      /// <summary>
      /// (Required) A code identifying the type of pattern that this dictionary describes;
      /// must be 2 for a shading pattern.
      /// </summary>
      [KeyInfo(KeyType.Integer | KeyType.Required)]
      public const string PatternType = "/PatternType";

      /// <summary>
      /// (Required) A shading object (see below) defining the shading pattern�s gradient fill.
      /// </summary>
      [KeyInfo(KeyType.Dictionary | KeyType.Required)]
      public const string Shading = "/Shading";

      /// <summary>
      /// (Optional) An array of six numbers specifying the pattern matrix.
      /// Default value: the identity matrix [1 0 0 1 0 0].
      /// </summary>
      [KeyInfo(KeyType.Array | KeyType.Optional)]
      public const string Matrix = "/Matrix";

      /// <summary>
      /// (Optional) A graphics state parameter dictionary containing graphics state parameters
      /// to be put into effect temporarily while the shading pattern is painted. Any parameters
      /// that are not so specified are inherited from the graphics state that was in effect
      /// at the beginning of the content stream in which the pattern is defined as a resource.
      /// </summary>
      [KeyInfo(KeyType.Dictionary | KeyType.Optional)]
      public const string ExtGState = "/ExtGState";

      /// <summary>
      /// Gets the KeysMeta for these keys.
      /// </summary>
      internal static DictionaryMeta Meta
      {
        get
        {
          if (Keys.meta == null)
            Keys.meta = CreateMeta(typeof(Keys));
          return Keys.meta;
        }
      }
      static DictionaryMeta meta;
    }

    /// <summary>
    /// Gets the KeysMeta of this dictionary type.
    /// </summary>
    internal override DictionaryMeta Meta
    {
      get { return Keys.Meta; }
    }
  }
}
